Not Just Developing Countries

The most interesting presentation I saw at the AEA last January was Maccini and Yang’s discussion of the effect of rainfall on the health and growth of Indonesian babies.* It was subsequently discussed as an NBER working paper** by Jason Shafrin, and the thing that made it most interesting is that Maccini and Yang found an effect on female children, but not one on male children.

But that’s a developing economy. Would the same type of thing happen in a developed nation?

Apparently, via Mark Thoma’s links, the answer is yes.

People who suffer from cardiovascular diseases at advanced ages may have reason to suspect that the cause of their illness lies far away … around the date of their birth. A team of European researchers reports that if economic conditions at the time of birth were bad, then this leads to a higher risk of cardiovascular mortality much later in life.

The researchers used Danish twins born around the turn of the (19th into 20th) century as their baseline. And the nature-nurture difference appears to be at the margin:

The twin data come with an added bonus. They make it possible to check whether a twin pair’s health outcomes are more similar later in life if they were born under adverse conditions than if they were born under good conditions. It turns out that, indeed, they are more similar later in life if the starting position was bad. Conversely, if an individual is born under better conditions, then individual-specific factors dominate more. In short, individual-specific qualities come more to fruition if the starting position in life is better.

The full paper is available here (PDF).

*The reasoning for such a study seems fairly straightforward: babies are most affected in their earlier years, rainy seasons—especially in subsistence-farming areas—should tend to produce a better crop yield and therefore marginally more calories available to babies. So the alternative hypothesis should be that rainy seasons produce healthier children, as reflected in schooling accomplishments and height, among other things.
**[Free version here; PDF]